Device For Filtration With A Set Of Least One Filter Cassette

ABSTRACT

The invention concerns a filtration device comprising a manifold providing fluid connection and mechanical connection comprising a clamping plate movably mounted relative to the manifold and adapted to compress at least one cassette against the manifold, means for driving and guiding the clamping plate comprising a rod extending between the manifold and the plate, an actuator provided with a body and a member moveable relative to the body, which member is adapted to move through a predetermined travel between an extended position and a retracted position, the body being carried by the manifold, and the member carrying the rod and driving the plate via the rod to a clamped position in which the member is in an intermediate retracted position in which it has moved through a shorter travel than the predetermined travel relative to its extended position.

This application is a continuation of U.S. Ser. No. 13/950,646 filedJul. 25, 2013, which is a divisional of U.S. Ser. No. 13/106,250 filedMay 12, 2011, which claims priority of French application No. 1053875filed May 19, 2010, the disclosures of which are hereby incorporated byreference.

The invention concerns devices for filtration of a liquid with a set ofat least one filter cassette, which liquid is for example a biologicalliquid, and particularly but not exclusively a biopharmaceutical liquid.

Patent EP 0 498 211 describes a filtration device which comprises amanifold providing fluid connection and mechanical connection, aclamping plate, four rods along each of which the clamping plate slides,a set of at least one filter cassette disposed between the manifold andthe clamping plate and means for clamping and locking to compress theset of filter cassettes between that manifold and that plate.

The manifold comprises a flow inlet for a fluid to treat, a filtrateflow outlet for a treated fluid termed filtrate, retentate flow outletfor a treated fluid termed retentate and a conveying network for thefluids to treat and the treated fluids. This manifold furthermore has abearing surface through which emerge ports communicating with theconveying network and communicating with conduits formed in the filtercassette abutting the bearing surface.

Each rod emerges from the bearing surface of the manifold and extendstowards the clamping plate.

The clamping plate is movably mounted on the rods, via four throughholes each formed substantially at a corner of that plate and eachreceiving a respective rod.

Each rod is threaded and four nuts are each screwed onto a respectiverod to form the clamping and locking means.

The nuts are screwed onto the rods to clamp the plate against the set ofcassette to reach a final position in which the set of filter cassettesis sufficiently compressed between the clamping plate and the manifold.

A drawback of this device is that the clamping of the set of filtercassettes is performed by hand.

A known solution to overcome this drawback is a filtration device whichcomprises, in place of the threaded rods, notched rods, and, instead ofthe nuts, hydraulic actuators and locking rings.

Each actuator comprises a body and a member that is moveable relative tothe body, which moveable member has an extended position and a retractedposition in which said moveable member has moved through a predeterminedtravel relative to its extended position.

These actuators are of single-acting or double-acting jack type, and themovement of the moveable member relative to the body is achieved byurging that moveable member in known manner.

Each actuator comprises its body which is fastened to the clamping plateand its moveable member which is mechanically linked to the notched rod,which rod extends between the clamping plate and the manifold where itis received through an aperture formed in that manifold.

Each locking ring is adapted to be engaged with a notch of a respectiverod.

The first step consists of advancing the clamping plate (and theactuator) from its starting position to the intermediate position inwhich the set of filter cassettes is not yet compressed, with therespective notched rod sliding through the aperture of the manifold.

The second step consists of connecting the rod and the manifold by themounting of the locking ring, which is split, on one of the notches ofthe rod to lock the rod relative to the manifold.

This split ring is mounted on the opposite side of the manifold to theside of the manifold facing which is the clamping plate.

The third step corresponding to fine clamping consists of urging themoveable member hydraulically to make it pass from its extended positionto its intermediate retracted position in which the moveable member hasmoved through a shorter travel than the predetermined travel relative toits extended position. As the moveable member is fixed to the notchedrod, itself fixed to the manifold which is fixed, the clamping plate isconsequently pushed by the body of the actuator to its final position.

A drawback of the known device with actuators is that the arrangement ofthose actuators increases the bulk of the device.

The invention aims to provide device for filtration with assistedclamping of the set of at least one filter cassette, which is simple,economical, convenient.

For this, according to a first aspect, the invention concerns a devicefor filtration with a set of least one filter cassette comprising:

a manifold providing fluid connection and mechanical connectioncomprising at least one flow inlet for a fluid to treat, at least oneflow outlet for a treated fluid and a network for conveying said fluidto treat and said treated fluid, said manifold having a bearing surfacefor a said filter cassette, through which bearing surface emergecassette feed ports and cassette return ports communicating with saidconveying network, which cassette feed ports and cassette return portsare configured to communicate with conduits formed in a said filtercassette bearing against said bearing surface;

a clamping plate; and

means for driving and guiding said clamping plate parallel to and facingsaid bearing surface, that are formed by at least one rod which extendsbetween said manifold and said clamping plate and by at least oneactuator, which is provided with a body and a member moveable relativeto said body, which moveable member has an extended position and aretracted position in which said moveable member has been moved througha predetermined travel relative to its extended position, by virtue ofwhich the clamping plate has a starting position in which said plate isaway from said set of at least one filter cassette and a clampedposition in which said plate is approached and compresses said set of atleast one filter cassette against said manifold;

said body is carried by said manifold; said moveable member carries saidrod; and said actuator, said rod and said clamping plate are configuredsuch that said actuator drives said clamping plate via said rod to itsclamped position in which said moveable member is in an intermediateretracted position in which said moveable member has moved through ashorter travel than said predetermined travel relative to its extendedposition.

Thus, in the device according to the invention, it is the manifold (andnot the clamping plate) which carries the body of the actuator.

By virtue of this arrangement, there is no actuator body projecting fromthe clamping plate on the opposite side to the rod. This for exampleenables the device according to the invention to be more compact,particularly, but not exclusively, if the extent of the actuator body interms of length superposes, at least partially, over the extent of themanifold in terms of thickness.

Furthermore, with this arrangement, there is no difficulty in uncouplingthe clamping plate and the rod, which makes it possible for example todispose that clamping plate in a position other than parallel to andfacing the bearing surface of the manifold, improving the accessibilityto the reception zone for the cassettes.

What is more, the proximal (and not distal) position of the actuatorfavors the installation of its supply conduits.

According to a particularly simple, convenient and economical feature,said rod and said clamping plate are configured such that said clampingplate can be selectively positioned along said rod.

Thus, the clamping plate is first of all moved from its startingposition to an intermediate position in which it is in non-clampingabutment against the set of filter cassettes, and is then driven by themoveable member to its final position.

According another particularly simple, convenient and economicalfeature, the device comprises two said actuators and two said rods, saidrods being received by said clamping plate in two diagonally oppositezones of that clamping plate.

Thus, the force exerted by the clamping means on the clamping plate, andconsequently on the filter cassettes, is distributed optimally over thewhole surface of that plate and thus over the whole surface of thecassettes.

According to preferred, simple, convenient and economical features ofthe device according to the invention:

the body of the actuator is directly fastened to the manifold; andoptionally

the manifold comprises two bearing surfaces arranged on respectiveopposite sides of said manifold, and two clamping plates each facing arespective bearing surface, and said clamping means comprise at leastone said actuator and at least one said rod for moving each saidclamping plate.

By virtue of the arrangement of the clamping means, and in particular ofeach actuator which is carried by the manifold, it is possible to placea set of filter cassettes on respective opposite sides of the manifoldproviding fluid connection and mechanical connection and to clamp themagainst respective bearing surfaces of that manifold, without howeverincreasing the bulk of the device.

To be precise, it is possible to mount several actuators at the locationof the manifold providing fluid connection, which actuators respectivelyact on one side and on the other of the manifold providing fluidconnection and mechanical connection so as to respectively approachtowards each other the clamping plates disposed on respective oppositesides of the manifold.

Thus, it is possible to greatly increase the biological treatment areasimply, conveniently and economically.

Of course, to increase the filtration area it is also possible tosuperpose the filtration devices, with their inlets and outlets incommunication. Care will then be taken to ensure sealing between twosuperposed filtration devices.

It will thus be possible to have a treatment installation comprising atleast one filtration device as described above, with filter cassettesover at least one side of each of the filtration devices.

It is thus possible for a user of that installation to adapt thefiltration area of each filtration device depending on the treatment toperform, simply, conveniently and economically.

Alternatively, according to other features preferred for the samereasons:

said body of the actuator is movably mounted in a sleeve fixed to saidmanifold; and optionally

said manifold comprises two bearing surfaces arranged on respectiveopposite sides of said manifold, and two clamping plates each facing arespective bearing surface, the clamping means comprise at least onesaid actuator, at least one said rod linked to one of the two saidclamping plates, at least one additional rod extending between said bodyof said actuator and the other of the two said clamping plates, saidadditional rod being carried by a first end by said body and, by asecond end that is an opposite end to the first end, carrying the otherof the two said clamping plates.

Thus, the same actuator serves to drive both the rod and the additionalrod situated on the opposite side.

According to another preferred feature, said rod comprises a pluralityof notches over its length.

The spacing of the notches on the rod may be regular or not. The lengthof the notches depends on the type of filter cassette used with theholding device. Furthermore, the length and the spacing of the notchesdepends on the travel of the jack, on the type and on the number ofcassettes, and on the degree of compression allowable for each cassette,which is approximately 10% of its thickness. The values corresponding tothe length of the notches and their spacing are determined in order forthe distribution of the fluid to be even in the filter cassettes. As tothe number of cassettes, this corresponds to the filtration area that itis possible to have over at least one side of the filtration device.This filtration area may range from approximately 1 m² to 10 m², and inparticular from 2.5 m² a 7.5 m². From one side of the filtration device,there will preferably be available approximately 5 m² of filtration areaformed by one or more filter cassettes.

According to other preferred, simple, convenient and economical featuresof the device according to the invention:

said device comprises a member for locking said clamping plate onto anotch of said rod;

said device comprises at least one rod for holding and guiding said setof at least one filter cassette which is carried by said manifold andwhich extends through at least one aperture formed in said clampingplate;

said device comprises at least one rod for supporting said clampingplate which is carried by said manifold; and/or

said device comprises means for mounting said clamping plate on saidsupporting rod comprising a slide and a hinge, by virtue of which saidclamping plate is slidingly moveable along the supporting rod and has aworking configuration in which it is raised parallel to and facing saidbearing surface and a stored configuration in which it is folded downand clear of said rod.

The disclosure of the invention will now be continued with thedescription of embodiments, given below by way of illustrative andnon-limiting example, with reference to the accompanying drawings, inwhich:

FIG. 1 is a perspective view of a filtration device according to a firstembodiment of the invention, with a clamping plate in storedconfiguration;

FIG. 2 is the section view on II-II of FIG. 1;

FIG. 3 is a similar view to FIG. 1, with the clamping plate in startingposition in which it is not yet clamped against the filter cassettes;

FIG. 4 is a side view of the device, with the clamping plate in clampedposition;

FIG. 5 is a perspective view of a device according to a secondembodiment of the invention, with the clamping plate in clampedposition; and

FIG. 6 is a diagrammatic view of a device according to a thirdembodiment of the invention;

FIG. 1 illustrates a device for filtration 1 with filter cassettes 2comprising a manifold 3 providing fluid connection and mechanicalconnection, a clamping plate 4 provided on a first side of the manifold3 to clamp the set of filter cassettes 2 between the manifold 3 and thatplate 4, and another clamping plate 34 provided on a second side of themanifold 3 that is an opposite side to the first side to clamp a dummycassette 26 (FIG. 4), means for driving each plate 4, 34 that are formedby notched rods 6, 36 carried by actuators 10 (FIG. 2), each plate 4, 34being disposed, in working configuration (FIGS. 3 and 4), parallel toand facing a respective bearing surface of the manifold 3, and beingmounted on the respective rods 6, 36.

Locking members 7, 37 are mounted on the notched rods 6, 36 to preventthe plate 4, 34 from moving in an opposite direction to the set ofcassettes 2 (FIG. 4).

Device 1 further comprises on each side of the manifold 3 rods 8, 38 forsupporting the respective clamping plates 4, 34 and means 9, 39 formounting the respective plates 4, 34 to make them slide and to make thempass from a storage configuration (FIG. 1) to a working configuration(FIGS. 3 and 4).

The device 1 further comprises on each side of the manifold 3 rods 5, 35for holding and guiding respectively the filter cassettes 2 and thedummy cassette 26.

In the example described, the device 1 forms part of an installation fortreatment by tangential filtration.

In tangential filtration, a fluid to treat enters the cassette 2 by afeed conduit 11 (FIG. 13), a first fraction of the fluid termedretentate flows tangentially to a membrane (not shown) of each cassette2 and a second fraction of the fluid termed filtrate passes through themembrane of each cassette 2 and flows perpendicularly to the retentate,then the filtrate and the retentate exit the cassette 2, respectivelyvia filtrate and retentate outlet conduits 12 and 13.

It is thus possible to retrieve different fractions of treated fluid,for example the filtrate or the retentate, depending on the type ofapplication.

It is to be noted that the cassettes 2 have identical opposite faces,with the same conduits of fluid to treat 11, filtrate 12 and retentate13 on each of those faces (FIG. 1).

The manifold 3 providing fluid connection and mechanical connection hasa substantially parallelepiped shape and is provided with a mechanicalpart of stainless steel and a fluidic part of plastics material, themechanical part comprising a space to receive the fluidic part.

This manifold 3 comprises two cheeks 14 each having two wings 15 facingeach other and a lateral wall linking the two wings 15.

The height of the cheeks 14 is at least equivalent to that of themanifold 3, and the space between the two wings 15 of each cheek 14 isequivalent to the depth of that fluidic part for its introduction bysliding into the space of the mechanical part of that manifold 3.

When the fluidic part is inserted into that space, an upper wall 16 isplaced on the upper face of the fluidic part of the manifold 3, thenscrewed by four fixing screws 17 inserted into the mechanical part ofthe manifold 3.

In the upper face of the fluidic part of the manifold 3 are formed aflow inlet 18 for the fluid to treat, a filtrate flow outlet 19 and aretentate flow outlet 20.

Around each inlet and outlets 18 to 20, are formed respective annulargrooves (not shown) adapted to receive seals (not shown) and pipes, forexample rigid stainless steel or flexible plastic pipes, for conveyingthe fluids to or from other parts of the treatment installation.

The fastening of the pipes onto these inlets and outlets 18 to 20 isprovided by linking units 21 mounted on the upper wall 16.

This manifold 3 is also provided with a lower face in which are formed aflow inlet and flow outlets similar to those on the upper face as wellas the same annular grooves and the same fastening units mounted on alower wall (not shown).

If it is wished to block off one of these inlets and/or outlets, itsuffices to insert a plug the annular rim of which is introduced intoone of those annular grooves.

The flow inlet 18, the filtrate flow outlet 19 and the retentate flowoutlet 20 respectively belong to a flow inlet conduit for the fluid totreat, to a filtrate flow outlet conduit and to a retentate flow outletconduit of the manifold 3.

These conduits are formed by machining, and in particular by boring thefluidic part of plastics material of the manifold 3, at least over amajor portion of its height.

Manifold 3 further comprises on its first side a first bearing surface22 against which a filter cassette 2 comes to bear.

On this first bearing surface 22 emerge cassette feed ports for thefluid to treat, cassette filtrate return ports and cassette retentatereturn ports (not shown), each of these ports moreover emergingrespectively into the flow inlet conduit, into the filtrate flow outletand into the retentate flow outlet conduit.

Manifold 3 further comprises on its second side a second bearing surface23 against which a dummy filter cassette 26 comes to bear.

No port emerges on that second bearing surface 23.

The manifold 3 providing fluid connection and mechanical connectionrests on a supporting plate 24 onto which it is fastened by fasteningscrews 25. This supporting plate 24 is adapted to be mounted in thetreatment installation, for example on a cart of that installation.

On each of the first and second sides of the manifold 3 providing fluidconnection and mechanical connection, the four rods 5, 35 for holdingand guiding the filter cassettes 2 are screwed at one end, respectivelyin pairs, in the respective wings 15.

The two respective holding and guiding rods 5 and 35 which project fromeach wing 15 of the manifold 3 are superposed such that, respectively,the set of filter cassettes 2 and the dummy cassette 26 may be held bythose respective rods 5, 35.

For this, each filter cassette 2 comprises on respective opposite sidesof its width, at the bottom, a semi-annular recess 27 having a shapecomplementary to the shape of the rod 5 which projects from the bottomof the cheek 14, and, at the top, a lug 28 which rests on the rod 5 thatprojects from the top of the lateral wall.

Naturally, the dummy cassette 26 is provided with the same lugs andrecesses as the filter cassettes 2.

Those rods 5, 35 for holding and guiding the filter cassettes 2 and thedummy cassette 26 are smooth so that those cassettes 2, 26 may easilyslide on those rods 5, 35.

From the first and second side of the manifold 3, each rod 8, 38 forsupporting the respective plate 4, 34 is screwed by a proximal end intoa respective cheek 14 of the manifold 3 and at the other, distal, end ofthe manifold 3 comprises respective abutment means 29, 33 each formed bya washer and a nut.

On each of the smooth rods 8, 38 for supporting the respective plate 4,34 are movably mounted respective mounting means 9, 39 for each plate 4,34.

Each mounting means 9, 39 has the form of a ring provided with a centralaperture passed through by a respective rod 8, 38 to form a slide.

Each mounting means 9, 39 is thus free to slide on the respective rod 8,38 between the manifold 3 and the respective abutment 29, 33.

Each mounting means 9, 39 further comprises a rotational shaft 40inserted into an aperture passing radially through that mounting means9, 39 to form a hinge.

Each plate 4, 34 comprises two feet 41 each mounted on a rotationalshaft 40 of the respective mounting means 9, 39 for the pivoting of thatrespective plate 4, 34.

Each plate 4, 34 is capable of passing very simply from a storageconfiguration to a working configuration as will be described below.

Each mounting means 9, 39 further comprises a protuberance 42 passedthrough by an aperture in which is inserted an abutment pin 43 for therespective clamping plate 4, 34.

Each pin 43 enables the respective plate 4, 34 to be horizontal in itsstorage configuration.

The manifold 3 has a third side and a fourth side that is an oppositeside to the third side, and which are formed by the cheeks 14, and thedevice comprises a casing 50 fastened to each of those cheeks 14, viafastening screws 51.

In the example described, each casing 50 is slightly offset towards thesecond side of the manifold 3 providing fluid connection and mechanicalconnection.

Each casing 50 comprises two actuators 10, of which one acts on thefirst side of the manifold 3 and the other acts on the second side ofthe manifold 3, as described below.

FIG. 2 more particularly shows the casing 50 of the third side of themanifold 3, where each actuator 10 comprises a body 52 which comprises achamber 54, a moveable piston 53 extended by a rod, that piston 53having an extended position and a retracted position in which themoveable piston is moved through a predetermined travel relative to itsextended position.

The actuators 10 are illustrated in retracted position in FIG. 2.

The actuators 10 here are double-acting hydraulic jacks disposed inparallel. For their supply, each casing 50 comprises two hydraulicconnectors 55 (FIG. 1).

One of the connectors 55 enables a liquid under pressure to be sent intoa first portion of the chamber 54, so as to urge the moveable piston 53to its extended position where it is at end of travel.

The other connector 55 enables a liquid under pressure to be sent into asecond portion of the chamber 54, this second portion being opposed tothe first portion, to urge the moveable piston 53 to the other end oftravel position, in its retracted position.

As can also be seen in FIG. 2, the actuators 10 provided for driving theclamping plates 4 and 34 are in superposed disposition in pairs in therespective casing 50.

Thus, the bulk of the device 1 may be extremely reduced on account ofthis arrangement.

As can be seen again in FIG. 2, the notched rods 6 and 36 are screwed atone end into a respective recess 56 provided in a rod which extends therespective moveable piston 53, the moveable piston 53 of the bottomactuator 10 driving the rod 6 extending from the first side of themanifold 3, and the moveable piston 53 of the top actuator 10 drivingthe notched rod 36 of the second side of the manifold 3.

In the casing 50 of the fourth side of the manifold 3, the top actuatoris linked via the rod extending its moveable piston to the rod 6 whichextends from the first side of the manifold 3, and the bottom actuatoris linked via the rod which extends its moveable piston to the rod 36which extends from the second side of the manifold 3.

As is particularly visible in FIG. 1, on the first and second sides ofthe manifold 3 providing fluid connection and mechanical connectionwhere filter cassettes 2 and the dummy cassette 26 are respectivelydisposed, the respective notched rods 6 and 36 are diagonally oppositelydisposed.

Each notched rod 6 and 36 has notches 30 regularly spaced over itslength.

The length of the notches depends on the type of filter cassettes 2 usedand the spacing of those notches depends on the travel of the moveablepiston 53 in the body 54 of the actuator 10, on the type and number offilter cassettes 2, and on the degree of compression that each filtercassette 2 can allow.

The clamping plates 4 and 34 each comprise four first through holes 31provided to receive the respective holding and guiding rods 5 and 35.

The clamping plates 4 and 34 further comprise two second through holes32 in diagonally opposite disposition and provided to receive therespective notched rods 6 and 36.

In the example described, the rods 5, 6 and 8 and 35, 36 and 38 thatrespectively extend from the first side and from the second side of themanifold 3 differ moreover in their lengths, the rods of the first sidebeing longer than the rods of the second side.

In a first step, the user installs the filter cassettes 2 on the rods 5,on the first side of the manifold 3 providing fluid connection andmechanical connection and installs the dummy cassette 26 on the secondside of the manifold 3.

During this step, the respective clamping plates 4 and 34 are in theirstorage configuration, that is to say that the respective mounting means9, 39 are in proximity to the manifold 3 and the plates 4 and 34 arerespectively horizontal to be moved under the respective supporting rods8 and 38.

Once the set of filter cassettes 2 and the dummy cassette 26 have beeninstalled, the respective clamping plates 4 and 34 are moved by slidingtowards the respective abutments 29 and 33 of the respective rods 8 and38, then each clamping plate 4, 34 is raised parallel to and facing thebearing surface 22, 23 to bring it into its working configuration.

The clamping plates 4 and 34 are then in their starting position inwhich they are respectively away from the set of filter cassettes 2 andaway from the dummy cassette 26.

Next, the clamping plate 4 is moved by sliding of the mounting means 9on each of the rods 8 until it is in non-clamping abutment against thefilter cassette 2 that is the furthest from the manifold 3.

The clamping plate is thus in an intermediate position in which itsprincipal internal surface 45 is situated in abutment against the filtercassette 2.

In parallel, the clamping plate 34 is moved by sliding of the mountingmeans 39 on the rods 38 to an intermediate position of that clampingplate 34 in which it is in non-clamping abutment against the dummycassette 26.

At that instant, each actuator 10 has its respective moveable piston 53in the extended position.

The locking members 7 and 37 are then mounted on the notches 30 situatedin immediate proximity to the respective clamping plates 4 and 34, onthe opposite side respectively to the set of filter cassettes 2 and thedummy cassette 26.

These locking members 7 and 37 have the form of a split ring, the splitscreating sufficient spacing for each ring 7, 37 to be mounted on therespective rod 6, 36 at the location of a notch 30, and have anappropriate thickness to remain in place at the location of that notch30.

Each locking member 7, 37 is thus fastened onto its respective rod 6,36, and the respective clamping plate 4, 34 thus faces an abutmentrespectively formed by those members 7, 37.

The moveable pistons 53 of the actuators 10 are then urged towards theirretracted position.

These moveable pistons 53 thus drive the rods 6, 36, and consequentlythe plates 4 and 34 which are locked via the locking members 7, 37 toprevent sliding on those rods, to the clamped positions of the clampingplates 4 and 34 in which those clamping plates 4 and 34 respectivelycompress the set of filter cassettes 2 against the first bearing surface22 of the manifold 3, and the dummy cassette 26 against the secondbearing surface 23 of the manifold 3.

In these clamped positions of the clamping plates 4 and 34, the moveablepistons 53 of the respective actuators 10 are in an intermediateretracted position in which each moveable piston 53 has moved through ashorter travel than the predetermined travel relative to its extendedposition.

The use of a dummy cassette 26 on the second side of the manifold 3,where there are no real filter cassettes, advantageously makes itpossible to perform even clamping of the whole set of cassettes on thefiltration device 1, and thus to improve the quality of the treatmentperformed.

To remove the set of filter cassettes 2 and/or the dummy cassette 26,operation is conducted in the opposite direction by urging the moveablepistons 53 towards their extended position so as no longer to place theset of filter cassettes 2 and the cassette 26 under compression byseparation of the respective clamping plates 4 and 34, then the lockingmembers 7 and 37 are removed, then the clamping plates 4 and 34 aremoved to their abutments 29 and 33 by sliding of the mounting means 9and 39 on the respective rods 8 and 38.

The user may also clean the device 1 and fold down the respective plates4, 34 to put them into their storage configuration.

The user may also clean the device 1, and in particular the manifold 3and the set of cassettes 2, while leaving that set of cassettes 2compressed.

FIG. 5 illustrates a second embodiment of the filtration device.

Generally speaking, the same reference numbers are used for similarparts but increased by 100.

In contrast with the filtration device 1 illustrated in FIGS. 1 to 4,the filtration device 101 illustrated in FIG. 5 comprises, on the firstand second sides of the manifold 103 providing fluid connection andmechanical connection, a set of filter cassettes 102 such that thefiltration area is increased.

There is thus no longer any dummy cassette in this embodiment.

The casings 150 comprising the actuators are fastened centrally on therespective cheeks 114, rather than being offset towards the second sideof the manifold 103.

The first and second sides of the manifold 103 are thus mirror images ofeach other.

This means that the supporting rods 108, the holding and guiding rods105 and the notched rods 106 are to be found on both those first andsecond sides of the manifold 103, those rods having the same length.

The putting into place of the cassettes 102 and the clamping operationsthereof are carried out in the same way as described earlier.

FIG. 6 illustrates a third embodiment of the filtration device.

Generally speaking, for similar parts the same reference numbers havebeen used as for the first embodiment, but increased by 200.

In contrast to the filtration device 101 illustrated in FIG. 5, thefiltration device 201 illustrated in FIG. 6 comprises a so-calledfloating actuator 210.

This actuator 210 is moveably mounted in a sleeve 260 fastened to thethird side of the manifold 203 providing fluid connection and mechanicalconnection.

The actuator 210 comprises a body 252 moveably mounted in the sleeve 260and a piston 253 moveable relative to that body 252.

The body 252 further comprises abutments 262 and 263 disposed onrespective opposite sides of the sleeve 260 to determine the travel ofthat actuator 210.

A notched rod 206 is fastened by a first end to the body 252 of theactuator 210 and linked by a second end, that is an opposite end to thefirst end, to the clamping plate 204 on the first side of the manifold203.

An additional notched rod 266 is fastened by a first end to the moveablepiston 253 of the actuator and linked by a second end, that is anopposite end to the first end, to the clamping plate 234 on the secondside of the manifold 203.

In this case, the body 252 drives the notched rod 206 which drives theclamping plate 204 to its clamped position in which it compresses theset of filter cassettes 202 against the first bearing surface 222 of themanifold 203, and the moveable piston 253 drives the additional notchedrod 266 which drives the clamping plate 234 to its clamped position inwhich it compresses the set of filter cassettes 202 against the secondbearing surface 223 of the manifold 203.

In the example described, a single actuator 210 is represented on thethird side of the manifold 203 providing fluid connection and mechanicalconnection.

In a variant not illustrated, the filtration device comprises anactuator 210 arranged on each of the third and fourth sides of themanifold 203 providing fluid connection and mechanical connection.

In still other variants not illustrated:

the fluidic part of the manifold is of stainless steel rather than ofplastics material;

the mechanical part of the manifold is of plastics material rather thanof stainless steel;

the mechanical and fluidic parts of the manifold are of plasticsmaterial, for example of polysulfone (PSU) or of polyoxymethylene (POM);

only one clamping plate is provided;

the actuator body or bodies is or are of an extent in terms of lengthwhich does not superpose over the extent of the manifold in terms ofthickness, for example by being fastened to the manifold by one end;

the hydraulic actuators are replaced by single or double actingpneumatic actuators, or are of a nature other than fluidic, for exampleelectrical;

the filter cassettes do not comprise lugs but are provided with severaladditional recesses, and these cassettes are for example of Pellicon®type, available from the Millipore company;

the clamping plate is removable rather than being linked to thesupporting rod by a mounting means mounted on that supporting rod;

the manifold is formed by molding rather than by machining, with itsflow inlets, flow outlets, conduits, cassette feed ports, cassettefiltrate return ports, and cassette retentate return ports being formedby injection molding;

the filtration device uses two filtrate flow outlet ports, one on theupper face and the other on the lower face, and the case arising one ofthe two filtrate outlet ports serves as a drain;

only two rods for holding and guiding the set of cassettes are disposedon at least one of the first and second sides of the manifold providingfluid connection and mechanical connection;

it is not tangential filtration that is carried out but for exampledead-end filtration for which a set of at least one cassette of POD®type is used, available from the Millipore company, or else viralfiltration for which a set of at least one cassette is used of MAGNUS®type, available from the Millipore company.

In still another variant not illustrated, the treatment installationcomprises several filtration devices as described above which aresuperposed, the set of filter cassettes on at least one side of themanifold providing fluid connection for each filtration device. It isthus necessary to connect several manifolds at the flow inlets andoutlets. These assemblies require sealing means at each junction betweentwo manifolds, at the location of the grooves formed around those inletsand/or outlets.

It is thus possible to adapt the filtration surface very simply to meetthe needs of that treatment installation.

It should be noted more generally that the invention is not limited tothe examples described and represented.

1. A device for filtration with a set of at least one filter cassettecomprising: a manifold having a substantially parallelepiped shape andproviding fluid connection and mechanical connection comprising at leastone flow inlet for a fluid to treat, at least one flow outlet for atreated fluid and a network for conveying said fluid to treat and saidtreated fluid, said manifold comprising two bearing surfaces arranged onrespective opposite sides of said manifold; said manifold furthercomprising at least one lateral side and an upper face and a lower faceopposite said upper face, wherein said at least one flow inlet and saidat least one flow outlet are formed in at least one of said upper faceand lower face; two clamping plates each facing a respective bearingsurface, through which bearing surfaces emerge cassette feed ports andcassette return ports communicating with said conveying network, whichcassette feed ports and cassette return ports are configured tocommunicate with conduits formed in a said filter cassette bearingagainst said bearing surfaces; and at least one guiding rod whichextends between said manifold and said clamping plates and at least oneactuator, which is provided with a body and a member moveable relativeto said body, which moveable member has an extended position and aretracted position in which said moveable member has been moved througha predetermined travel relative to its extended position, by virtue ofwhich the clamping plates have a starting position in which said platesare away from said set of at least one filter cassette and a clampedposition in which said plates are approached and compresses said set ofat least one filter cassette against said manifold; said body of said atleast one actuator being mounted on said at least one lateral side;wherein said body is carried by said manifold; said moveable membercarries said guiding rod; and said actuator, said guiding rod and saidclamping plates are configured such that said actuator drives saidclamping plates via said guiding rod to their clamped position in whichsaid moveable member is in an intermediate retracted position in whichsaid moveable member has moved through a shorter travel than saidpredetermined travel relative to its extended position.
 2. A deviceaccording to claim 1, wherein said guiding rod and said clamping platesare configured such that said clamping plates can be selectivelypositioned along said guiding rod.
 3. A device according to claim 1,comprising two said actuators and two said guiding rods, each saidguiding rod being received by a clamping plate in two diagonallyopposite zones of said clamping plate.
 4. A device according to claim 1,wherein said body of said actuator is movably mounted in a sleeve fixedto said manifold.
 5. A device according to claim 4, further comprisingat least one additional rod extending between said body of said actuatorand the other of the two said clamping plates, said additional rod beingcarried by a first end by said body and, by a second end that is anopposite end to the first end, carrying the other of the two saidclamping plates.
 6. A device according to claim 1, wherein said guidingrod comprises a plurality of notches over its length.
 7. A deviceaccording to claim 6, further comprising a member for locking each saidclamping plate onto a notch of said rod.
 8. A device according to claim1, further comprising at least one holding and guiding rod for holdingand guiding said set of at least one filter cassette which is carried bysaid manifold and which extends through at least one aperture formed ineach said clamping plate.
 9. A device according to claim 1, wherein saiddevice comprises at least one supporting rod for supporting saidclamping plate which is carried by said manifold.
 10. A device accordingto claim 9, further comprising a slide and a hinge, by virtue of whicheach said clamping plate is slidingly moveable along the supporting rodand has a working configuration in which it is raised parallel to andfacing said bearing surface and a stored configuration in which it isfolded down and clear of said guiding rod.